The present disclosure relates generally to semiconductor manufacturing. Specifically, the present disclosure relates to a semiconductor device having a microstructure device having an enhanced anchor along with a method of fabricating the same.
The semiconductor integrated circuit (IC) industry has experienced rapid growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. However, these advances have increased the complexity of processing and manufacturing ICs and, for these advances to be realized, similar developments in IC processing and manufacturing are needed. In the course of IC evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometry size (i.e., the smallest component that can be created using a fabrication process) has decreased.
Microelectromechanical systems (MEMS) devices are very small electro-mechanical systems incorporated into semiconductor IC circuits. One example of a MEMS device is a micro-inertial sensor. Conventional silicon on insulator (SOI) type MEMS devices are fabricated using a buried oxide layer as a sacrificial material layer. As such, the oxide layer is removed at a later stage of fabrication where the amount of oxide to be removed is time controlled. Drawbacks of this approach include 1) uniformity of the undercut etching is hard to control during fabrication, which 2) creates a wide undercut under the anchor area, and 3) does not produce a narrow air gap structure (e.g., <200 nm).
Therefore, what is needed is an improved microstructure device with an enhanced anchor, and a method of fabrication.